''Albertatherium'' (meaning "beast of

Alberta Alberta is a Provinces and territories of Canada, province in Canada. It is a part of Western Canada and is one of the three Canadian Prairies, prairie provinces. Alberta is bordered by British Columbia to its west, Saskatchewan to its east, t ...

") is an extinct genus of alphadontid

metatherians Metatheria is a mammalian clade that includes all mammals more closely related to marsupials than to placentals. First proposed by Thomas Henry Huxley in 1880, it is a more inclusive group than the marsupials; it contains all marsupials as well ...

that lived during the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

. The genus contains two species, ''Albertatherium primus'' (the type species), and ''Albertatherium secundus''. Fossils have been found in the Eagle Formation of

Montana Montana ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Idaho to the west, North Dakota to the east, South Dakota to the southeast, Wyoming to the south, an ...

and the

Milk River Formation The Milk River Formation is a sandstone-dominated stratigraphic unit of the Western Canada Sedimentary Basin in southern Alberta, Canada. It was deposited in near-shore to coastal environments during Late Cretaceous (late Santonian to early Campa ...

of Alberta.

Taxonomy

''Albertatherium'' is a member of the

Alphadontidae Alphadontidae was a family of mammals belonging to the clade Metatheria Metatheria is a mammalian clade that includes all mammals more closely related to marsupials than to placentals. First proposed by Thomas Henry Huxley in 1880, it is a ...

, an extinct family of metatherians closely related to marsupials. Recent phylogenetic studies group it with other northern non-marsupial metatherians such as ''

Alphadon ''Alphadon'' is an extinct genus of small, primitive mammal that was a member of the metatherians, a group of mammals that includes modern-day marsupials. Its fossils were first discovered and named by George Gaylord Simpson in 1929. Description ...

'' and '' Turgidodon''.S. Bi, X. Jin, S. Li and T. Du. 2015. A new Cretaceous metatherian mammal from Henan, China. PeerJ 3:e896 A 2016 phylogenetic analysis is shown below.

References

{{Taxonbar, from=Q3825052 Prehistoric metatherians Prehistoric mammal genera Late Cretaceous mammals of North America Paleontology in Alberta Cretaceous Canada Fossils of Canada Paleontology in Montana Cretaceous United States Fossils of the United States Milk River Formation Fossil taxa described in 1971